Classifier



Nov- 14, 1933. J. M. MITCHELL CLASSIFIER Filed Jan. 3. 1929 2 Sheets-Sheet l awe whom Nov. 14, 1933.

J. M. MITCHELL CLASSIFIER Filed Jan. 3. 1929 2 Sheets-Sheet 2 w w duz Inthese drawings: e

Patented No 14, 1933 1 j .um'ren. 2 r

1,934, 12 (IJLASSIFQIER JamejMacdmiam Mitchell, Flushing, vly; Application January 1929. s rial No. 330,05;

12 claims,

{This invention relates toclassifiers and, more 7 particularly, to apparatus for classifying and dewatering fine material carried in a liquid.

The principal object of the inventionis to pro- 354? 'vide apparatus for the treatment of fine, material-:in a liquid to effect-a classification of the material and simultaneouslyremove the-liquid therefrom. j 1 1 yAnothGIf Object is to provideapparatus of: the

veyer in the form of a belt uponvwhich the material to be classified is depositedand which-is of such construction that in the course oi? travel of 'the'belt, liquid will drain from the' material al and the material will :settle upon: the belt and will be classifiedas course, medium and fine; v Axfurther objectg of the inventionis to provide apparatus; oi the character set forthineluding a belt conveyer, which is trough-shaped '29 or concave in -cross -se'ction and which travels '25 material settled out.-,

1 I Other objects and advantagesof theiinvention will in; parto be obvious and a in part more fully I brought out as the descriptionproceeds.

In the,accompanying drawings; I have illus- 39 trated a practical embodiment of my-invention;

but it is to be understood that thedrawings are illustrative merelyand arenot be construed as limiting the invention tojthe particular details of construction thereinshown. It will be readily invention is susceptible'aoi embodiment in a variety of forms without sacrificing any of the advantages -of the invention or departing iromthe scope thereof as defined in the appended claims.

, :Fi l is a plan viewof a classifying apparatus constructed -.-in ,ac c ordan ce with my 1 invention;

5 Fig. 3 is a sectional view taken isubstantially along line 3-3 of Fig. 1. a H

-; Referring, now, to the drawings, the reference? numeral 1 indicates generally a irame-work which may be of, anysuitable construction and 5 which is eomposed-of, uprights and eross-pie ces suitably arranged to form a rigid supporting frame. i

' ,Suitablymounted in the ,frame at one end is a drive roll or'p'ulley 2 which is' driven by a belt 3 which receives its motion from any convenient 110 character above set forthrwhi chincludes a con-' 5 appreciatedby thoseuskilled'inf theart that thesource ofmotive power. At the opposite end of theaframeis mounted a head-pulley or roller 4, and at the lower end of the frame are mounted guide-rolls 5 and'6; v Thereference-numeral {7 indicates generally a conveyorjof the endless type which is trained about the drive-pulley or roller 2 and the headpulley 4,' and which is suitably guided in its moverjnentby the guide-rollers 5 and 6. I The conveyor 7 may bein the form of ajcontinuous, onepiece belt, provided along 'its'longitudinal center with openings 8 for the'esc ape of liquid. I-Iowever, Iprefer to construct the conveyor '7 ofytwo belts of equal length and which are so trained about various pulleys as to providespace between their adjacent edges and'thusproduce a continuousfdischarge Opening for thefliquid The two; belts are secured in spaced relation by Ineansof suitablesecuring elements or straps 9 which are riveted or otherwise fastened to the respective beltsll. By this means, the conveyor,jalthough constructed of two separatebelts, is in fact a unitarystructure and travels as such during the operation of the apparatus. a

Upon theupper part of the iramework, have provided a pluralityjof idlers 10 which support the upper or operating portion of the conveyor.

As indicated in Fig. 2, theidlers 10 are mounted in pairs upon supports '11 which are pivoted as at .12 to certain crosspiece's of theframe- 'work. Upon the bottom surface of each of the supports 11 I have provided an inclined projection or wedge 12 which cooperates with a mov-' able wedge 13, the arrangement being such that as the' wedge 13 cmovesinwardly or outwardly withrespect to the center of the apparatus, the

rangement asdisclosedinFig. '2, it will now be apparent thatmthe contour of the conveyor 7 vmay be varied by adjustment of the idlers 10. Inactual operation ofthe apparatus theidlers 10 will be so adjusted as to impart to the, con,-

-veyor a concave: cross-sectional area. In other words, the conveyor may be said to be troughshaped. ,By moving thewedges 13 outwardly from the'center of the apparauts, it will be seen that theinner idlers' l0'will beprop ortionately lowered and, thus, a more decided trough is imparted to the conveyor. Ihe pur e ofiflgi suit that when'the material reaches. the headthe feed boxes 16 to the conveyor 7 over inclined aprons 17.

When the material is deposited upon the conveyor '7, it will be apparent that the liquid will. flow towards the center of the conveyor and will escape through the openings 8 and will be 001- lected in a waste-waterlaunder 18 suitably sup [means connecting and maintaining the belts in ported in the framework 1. By reason of :the slope of the sides of the conveyor towards the center, it will be apparent that since the outside edges have the greatest departure from the horizontal, the speed of travel of the water 2 will decrease as it fiows towards the center. The rate of flow .of the water is also affected by. the fact that it will spread out and, consequently, be more shallow near the center, and there will be some loss of speed due to friction. The result.

is that when the material, for example sand in a liquid, is deposited upon the edges of the conveyor, the liquid will start to flow towards the center thereof. The coarser particles of the material will at once settle upon the conveyor near the outer edge and the grade of material will become gradually finer towards the center of the conveyor by reason of thefact that more time is allowed for'the material to settle out. Of course, the very finest particles will be carried by the liquid through the openings '8 and into the waste-water launder 18.

During the operation of the apparatus, it is, of course, understood that the conveyor travels. in a horizontal plane from right to left, as indicated in Fig. 3. During the. course of its travel, the

liquid constantly flows down the sides of the con veyor and into the escape openings, withthe repulley 4, it has been substantially de-watered and is arranged upon the conveyor in such a manner that the coarserparticles are near the outsideedges thereof and the finer ones near the center. As the conveyor. travels over. the headpulley 4, the material drops off and is collected insuitable hoppers19. f

The depths of the trough of the conveyor 7 may be varied from'time to timeby adjustment of the idlers, as heretofore described, 'so 'asIto renderthe apparatus useful for any desired classification. For-example, if it is desired to settle out only coarse sand from the material fed to the conveyor, the idlers will be so.adjusted as to provide a trough of such de pth that the liquid will flow rapidly through the discharge openings. This will permit only sufiicient time for the settling of the. heavier or coarser particles. If ,a very fine classification of the material is desired, the trough will be made very shallow, so as to provide for a slow flowing of the liquid towards the discharge openings. This will give even the finer particles sufficient time angular 'relationship of certain of said idlers of pairs of angularly-adjustableidlers for supand thereby vary the cross 'se'ctional contourof modifications thereof which will come within the scope of the appended claims."

What I claim is: V

1. Apparatus for classifying material in a liqquid, including a pair of belts spaced to provide between them an opening for the escape of liquid, means for imparting motion to said belts, means to maintain said belts in predetermined spaced relation and effective to cause said belts to move as a unit, and means for varying the angular relation of the belts.

2. Apparatus for classifying material in a liqquid, including a pair of angularly related belts,

- each of said'belts, and means for adjusting said supporting meanstovary the angular relationshipof the belts.

3.Appara'tus for classifying material in a liquid, including a conveyor composed of a pair of belts-connected'together in spaced relation, means for supporting each' ofthe belts, and means for-adjusting said supporting means to vary the contour of said conveyor. 4. Apparatus for classifying material in a liquid, including a conveyor composed of a pair of spaced belts connected at intervals,- a plurality of independent angularly adjustable idlers for ion supporting said belts, andmeans to adjust the whereby to vary'the contour of said conveyor.

5. Apparatus-for classifying material ina liquid, including .a pair of angularly related belts connected together in'spaced relation, a plurality porting said belts, and'm'ean's to.- adjust the angular relationship of the idlers ofeach pair to thereby vary the angula relationship of the belts. 6. Apparatus for classifying material in a liquid, including a frame,- rollers supported in said frame," an endless conveyor trained about'said rollers and composed of a' pluralityof belts connected together" in'spacedrelation, a plurality, of idler supports pivotallymounted on said frame between said rollers, idlers on saidsupports, and means for turning said supports about their respective pivots to vary'the'angle of the idlers said conveyor.

7. Apparatus for classifying material in a liquid, including aframe, rollers supportedin said frame, anendless conveyor trained'aboutsaid rollers, 'a plurality of idler supports pivotally mounted on said frame between said rollers, idlers 130v on saidsupports,f a wedge secured to each of said supports, andjmovable wedges mounted 'in' said frame'andadapted to cooperate with the wedges on said supportsto turn said supports about their respective pivots.

8. Apparatus for classifying material in-a liquid, including an endless'conveyor of concave transverse cross-section andprovided with openings located centrally between its edges for the escape of liquid, and means for depositing material in a liquidupon said conveyor at the outer edges thereof, whereby the-liquid will flow at gradually decreasing speedtoward said escape iio openings and'th'e materialwill be gradually deposited upon said conveyor, the coarser material at the edges and the finer material nearer to the escape openings. I I x 9. Apparatus for classifying material in a liquid including a' conveyor composed of a pair Q Endless belts connected at intervals by cross pieces, supporting means for each of the belts, and means for varying the angular relation of the supporting means to vary the cross sectional contour of the conveyor.

10. Apparatus for classifying material in a liquid including an endless conveyor formed with central discharge openings, supporting members disposed beneath the conveyor on each side of the-discharge openings, and means for varying the angularrelation of the supporting members to vary the cross sectional contour of the conveyor. V f 11. Apparatus for classifying material in a liquid, including a belt conveyor having a central longitudinal opening dividing the conveyor into spaced longitudinal sections, idler rolls supporting each section of the conveyor for, asubstantial portion of its width inwardly of its edges, the rolls at their inner end terminating short ofthe opening between the sections, andmeans to adidlers mounted upon said frame between said rollers for supporting each section of the conveyor, said idlersextending for a substantial portion of the width of the conveyor sections but terminating short of the central opening, and

tionalcontour of said conveyor relative to the centralopening. I

' JAMES MACDONALD MITCHELL.

,means to adjust said idlers to vary the cross-sec- V 

